A&P Exam 4 (Abdomen and Vasculature of the Abdomen)

Describe the inferior epigastric artery with regard to: origin, region of the body it supplies, vessel with which it anastamoses. (X144-X145)

- arises from the external iliac and runs superiorly to enter the rectus sheath. It supplies the lower part of the rectus abdominus - anastomosis between the superior and inferior epigastric arteries is approximately in the umbilical region - additionally, the superficial epigastric artery provides arterial blood supply to the subcutaneous tissue over the suprapubic region. It arises from the femoral artery

Name the unpaired visceral branches of the abdominal aorta. State the organ(s) each supplies. (X154)

- celiac trunk - superior mesenteric - inferior mesenteric

celiac trunk

- left gastric: stomach and esophagus - splenic: spleen, pancreas, greater omentum and stomach - common hepatic: liver, gallbladder, stomach, duodenum, pancreas and greater omentum

Superficial dissection of anterolateral abdominal wall

- most fibers of the external oblique muscle run inferomedially-in the same direction as the fingers do when the hands are in one's side pockets - the anterior superior iliac spin of the ilium is an easily palpable landmark

Name the two vertical muscles that are located in the anterior abdominal wall. What structure contains the vertical muscles? How is this structure formed? (X130, X132-X135)

- rectus abdominus - pyramidalis Formation of the rectus sheath is illustrated in the upper right diagram. The rectus sheath consists of fused or interlaced aponeuroses of the three flat muscles of the anterolateral abdominal wall, which form a fibrous compartment around the rectus abdominis and pyramidalis muscles.

Given an illustration, diagram, or word description of abdominal arteries, identify: abdominal aorta, celiac trunk, common iliac artery, external iliac artery, internal iliac artery, renal artery, superior mesenteric artery, inferior mesenteric artery. (X152.2)

- the abdominal aorta is a continuation of the thoracic aorta - it begins at the aortic hiatus in the diaphragm - it ends about the level of the fourth lumbar vertebra where it divides into right and left halves the become the common iliac arteries

Name the paired visceral branches of the abdominal aorta. State the organ(s) each supplies. (X153)

- the middle suprarenal arteries - the renal arteries - the gonadal arteries

Name the three flat muscles that are located in the anterolateral abdominal wall. (X130-X131)

-external oblique -internal oblique -transverse abdominal

Arrange the following veins in sequence: common iliac vein, external iliac vein, inferior vena cava, internal iliac vein. (X167)

1) internal and external iliac veins drain into the common iliac vein 2) common iliac vein drains into the inferior vena cava

portal system

formed when one venous capillary coalesces and then branches out to form another capillary system without the heart being between them the two portal systems in the body are the hepatic portal system and the hypophyseal portal system

State the function of each of the following venous vessels of the abdominal region: hepatic vein, inferior vena cava, mesenteric vein(s), portal vein (hepatic portal vein), sinusoids (liver sinusoids). (X170-X179)

hepatic vein: after passing through the liver for processing, blood drains into the hepatic veins which empty into the inferior vena cava inferior vena cava: major system that receives blood from the hepatic vein mesenteric vein: capillaries of the intestine coalesce to form the inferior and superior mesenteric veins portal vein: the coalesced mesenteric veins sinusoids: the portal vein then leaves the liver to form the sinusoidal capillaries

superior mesenteric artery

pancreas, duodenum, jejunum, ileum, ascending colonand transverse colon

inferior mesenteric artery

transverse colon, descending colon, sigmoid colon and rectum

Describe the muscles of the anterolateral abdominal wall with regard to: action, motor innervation, orientation of fibers. (X131-X137)

There are two vertical muscles of the anterolateral abdominal wall: the rectus abdominis and the pyramidalis. The rectus abdominis is the principal vertical muscle of the anterior abdominal wall. It is a long, broad straplike muscle that originates at the pubis and inserts on the xiphoid process and 5th to 7th costal cartilages. Actually, this is a paired set of muscles that lie close to each other, separated by the linea alba. Its function is to flex the trunk. It also compresses abdominal viscera, and in so doing acts as an antagonist of the diaphragm to produce expiration. Three or four tendinous intersections are present. In muscular persons flexing the muscle causes the muscle to bulge between the intersections. The pyramidalis is a small triangular muscle that is absent in about 20% of people. It is anterior to the inferior part of the rectus abdominis, and attaches to the anterior surface of the pubis and ends in the linea alba. It tenses the linea alba. Formation of the rectus sheath is illustrated in the upper right diagram. The rectus sheath consists of fused or interlaced aponeuroses of the three flat muscles of the anterolateral abdominal wall, which form a fibrous compartment around the rectus abdominis and pyramidalis muscles. The linea alba is a fibrous band running vertically the length of the anterior abdominal wall. It receives the attachments of the oblique and transverse abdominal muscles. It also contains small blood vessels and nerves that go to the skin.

Arrange the following layers of the abdominal wall in sequence from superficial to deep (some may be present more than once, and some are alternative terms for the same structure): endoabdominal fat layer, external oblique muscle, extraperitoneal fat layer, fascia, internal oblique muscle, skin, superficial fatty tissue, transverse abdominal muscle. (X131)

a) skin b) fatty layer c) membranous (deep) layer of superficial fascia (Scarpa's) d) external oblique muscle e) deep fascia f) internal oblique muscle g) deep fascia h) transverse abdominal i) transversalis fascia j) endoabdominal (extraperitoneal) fat i) parietal peritoneum